Process for manufacturing preserved fruits



May 1, 1962 D. J. LIMPERT PROCESS FOR MANUFACTURING PRESERVED FRUITSFiled Sept. 11, 1958 R S Y 0% E T N mm m vL N w l A 1 m Y M s Arm infi

Tim i concentrated hot sugar solution.

United States This invention relates to improvements in the manufactureof preserved fruits of the type in which sugar is stored in the fruitand more particularly to a process for manufacturing maraschinocherries.

A number of different processes have been proposed for the manufactureof preserved fruits, including the manufacture of maraschino cherries.In general, processes producing satisfactory products are slow andtedious and in many instances take four to six weeks to build up therequired amount of sugar in the fruit. In known processes formanufacturing maraschino cherries, six weeks are required to attain theusual content of 50% sugar. 7 1

However, according to some proposals, fruit is impregnated with sugar ina short period of twenty hours or a few days by heating the fruit toboiling and using a hot In one such proposal a ton of fruit'wasdescribedas being processed hot in a single container. But, such processescollapse the structure of the fruit and soften the tissues resulting innonuniform products having an appearance of low quality, particularlywith fruits of the type of cherries.

The primary object of the present invention is to provide an improvedprocess by which maraschino cherries and other fruits containing 50%sugar or more are produced in a relatively short period of time.

A further object of the invention is to provide a process which resultsin the production of a high yield of maraschino cherries and similarfruits of the highest quality which are round, plump, tender and crisp.

A further object of the invention is to provide a process which willovercome the problem of crushing or mashing the fruit during processingand provide a process which treatment, according to known procedure, arecontacted with an air-free water solution of sugar at ordinary roomtemperatures, advantageously while maintaining the cherries inrelatively shallow horizontal layers. The use of such shallow layers inconjunction with other conditions of the process has been found toprevent crushing and compacting during processing. The sugar solution iscirculated from a sugar dissolving chamber, where sugar is dissolved bythe solution, through the cherries filled into containers, for exampledrums arranged in parallel, and back to the dissolving chamber. In thisoperation the dissolving chamber or zone contains a body of sugarsolution and is preferably elevated above the drums of cherries, so thatcirculation is by gravity and automatic. The solution is circulatedcontinuously through the system for a period of approximately two tothree weeks to complete the deposition of the required amount of sugarin the cellular structure of the cherries or other fruit.

In the initial stages of the operation at least, the solution flowingfrom the containers of cherries to the sugar dissolving zone ispreferably heated sufficiently to cause removal of the absorbed aircontent of the fruit which the solution collects. The solution cools toroom temperature by the time it reaches the fruit in the containers.

During the circulation of the solution through the layers of fruit, aportion of the sugar content of the soluatent tee tion is deposited inthe cellular tissues of the fruit by the process of osmosis, the sugarsolution gradually replacing the normal moisture or water content of thefruit. As this replacement occurs, the solution flowing back to thesugar saturating chamber contains about 2% less sugar than the solutionflowing from the chamber to the layers of cherries.

The improved process includes other important features and conditions asdescribed more in detail hereinafter in connection with the accompanyingdrawings, in which:

FIG. 1 is a diagrammatic elevational view of an apparatus arrangementsuitable for use in carrying out the improved process; and

FIG. 2 is a cross-sectional view taken on the line 2-2 of FIG. 1.

The apparatus shown diagrammatically in FIG. 1 comprises an open-toppedchamber 10 used for dissolving granulated sugar in the solution beingcirculated in the system. The chamber 10 is provided at the bottom withan outlet pipe 12 which is connected into a header pipe 14, preferablyat about its midpoint. A plurality of connecting pipes 16 connect intothe header 14, and serve to conduct sugar solution in parallelrespectively to the lower portions of processing drums 18. An outletpipe 2% is connected into the upper portion of each drum 18, and all ofthese pipes are connected in parallel into a return header 22, connectedby a pipe 24 into a horizontal pipe 26, which at the left, is connectedby a riser pipe 28 into a heating chamber 30 provided with a heatingcoil or unit 32. The upper end of the chamber 32 is provided with anoverflow pipe 34 opening into the upper portion of the chamber 10. Theopposite end of the horizontal pipe 26 is connected into an overflowriser pipe 36 leading to a tank (not shown) and which determines theliquid level in the chamber 10.

The heads of the drums 18 or the ends of the pipes 16 and 20 openingthereinto are provided with perforated plates or screens 38 to preventaccess of cherries to these pipes. The pipes 16 and 20 may be flexibleand are also provided with suitable valves, not shown, so that the drumsmay be disconnected for emptying and refilling or for direct shipping atthe end of a processing operation. Any suitable type of connections maybe provided and removable heads 39 are preferably provided which clampto the drums and facilitate the connection of filled drums into thesystem.

Each drum 18 as shown in detail in FIG. 2, is provided with areadily-removable internal shelf grid structure, so that the cherriestherein are maintained in relatively thin layers not exceeding from 6 to8 inches in depth, with the drums placed horizontally or on a slightincline during processing, as shown in FIG. 1. This grid structurecomprises similar vertically-spaced perforated shelf plates 40 and 42secured to and held in spaced parallel relation with respect to eachother by a vertical plate or plates 44. The shelf plates 40 and 42extend from one end of the drum to the other and to the wall on oppositesides of the drum in a symmetrical relationship, so that the body ofcherries filled into each drum is divided into three superposed layers.In each instance, removable heads are secured so that the solution inletpipe 16 opens into the drum below the lower shelf plate 42, while theoutlet pipe 20 is connected into the drum above the upper shelf plate40. The drums 18 are advantageously set preferably at a slight inclineapproximating 5 to the horizontal, as shown in FIG. 1, favoring the flowof the saturated solution downwardly along the bottom of the drum andthe flow of the more dilute solution up wardly along the top of thedrum.

In arranging the apparatus, the headers 14 and 22 are with the solution.

provide a pressure head adapted to effect automatic circulation in thesystem. In the drawings the direction of flow is indicated by thearrows.

The drums 18 are preferably all 'at the same level and are convenientlylocated on one floor of the building, housing the equipment, whereas thesugar saturating chamber is located on the floor above. The saturatingchamber 10 is provided with ascreen 46 supported on the upper rim of thechamber 10 and extending down into the chamber to a point below theoverflow 34. The lower part'of the screen has a corrugated formation at48 to provide an extensive screen surface in contact The screen 46 is offrom 40 to 80 mesh and adapted to retain granulated sugar, a mound ofwhich is shown at 50. At intervals during the process a IOO-pound bag ofgranulated cane or beet sugar is dumped onto the screen so that a moundof sugar is always maintained on the screen'cn during a run.

In starting up the apparatus as described above for carrying out theprocess of the invention, for example for the production of maraschinocherries, the forty drums,'or a determined number of drums for theparticularrun are each filled with a predetermined weight of preparedcherries, with the drum heads removed and the removable dividersinserted, the weight being determined by the sizes and characteristicsof the cherries.

"An important factor in filling the drums is that the drums are notfilled to an extent which would crowd the cherries during processing.After the drums are filled, they are connected up into the system bysecuring the removable heads, then the drums are set in the mannerdescribed above and shown in FIG.- 1 of the drawings. When the drums areall connected into the system, the system is entirely filled with wateruntil water runs out of the overflow through the pipe 36. At this pointgranulated sugar is dumped onto the screen 46, the desired flavor andcoloring materials are placed in the chamber 14 and the heater 32 isturned on.

The sugar placed on the screen 46 begins to dissolve through the'screenand circulation in the system commences. Since the sugar solution asformed is more dense than the surrounding water, it slowly settles andflows through the pipes 12, 14 and 16 to the drums filled with cherriesand water. This flow forces the water already in the system from thedrums through the pipes 20, 22, 24, 26 and 28. the heater 3% and pipe 34into the kettle or chamber-10. Any excess water in the system and thatreplaced in the cherries overflows'through the pipe 36 at the levelindicated.

As the circulation continues, the sugar solution becomes progressivelymore concentrated. For example, during a run, the sugar solutionreturning to the chamber 10 through pipe 34 is only about'l /z to 2%lower in sugar content than that of the solution flowing down throughthe pipe 12. V In the course of a run of from about 2 to 3 weeks for theintroduction of maraschino cherries, the solution flowing through thepipe 12 finally reaches a concentration of about 50% sugar. Over thewhole period of a 'run, the cherries in the drums have a sugarconcentration only 2% or less below the concentration of the reinforcingsyrup flowing to the drums 18 from the chamber 10.

The sugar syrup flow is continuous, rapid and level throughout thesystem. For example, the rate of flow through the pipe 34, a 2-inch LD.pipe, is approximately IOOgallons per hour. As the circulation proceedsduring a run, the sugar is replenished on the screen 46, and theoverflow takes off the water and syrup displaced by the added sugar.During the whole period of the run, there is a continuous flow with theheaviest syrup finding its way to the bottom of the system in the drumswhere the cherries are located, displacing water driven off, as well aslighter syrup which rises to flow back through the heater 3t? and drumit), the excess flowing out of the system into tanks through theoverflow 36.

The heater 3% warms the syrup returning to the kettle or chamber 10 to atemperature of about 140 F. This heating-releases the air dissolved bythe water or syrup from the cherries. The warm water or syrup flowingfrom-the heater into the kettle or chamber 10 facilitates the dissolvingof sugar from that on the screen 46. The heater 3% has only a smallcapacity, and is not intended to and does not heat the cherries at all,since by the time the syrup is mixed in the chamber 10 and travels thedistance to the drums 18, at the rate of circulation, the syrup iscooled to room temperature.

The heating of the syrup at a particular point in the system, followedby the removal of air from the syrup, gives the syrup an increasedcapacity t0 dissolvemore air as it cools and returns to the layers ofcherries in the drums. The cool, reinforced syrup returning to thecherries in the drums dissolves any air which may be trapped either inthe pit cavities'or in the cellular tissues of the cherries. As the warmsyrup gives 01f its air, when his delivered into the chamber 10, a layerof foam is formed on the top of the'solution in the kettle, whichpersists for about six days during the run. After the air in thecherries has been completely removed, the foam on the kettle subsidesand the syrup becomes crystal clear. The processing continues for theentire run, gradually and imperceptibly increasing the sugarconcentration without heating'or crushing the cherries in the drums.

At the end of'the run, the drums ofmaraschino cherries are stood uprightand disconnected from the system. The drum heads 39 and connections areremoved, the removable dividers are pulled out and the drums of finishedcherries, together with the syrup content are sealed up withstandarddrum heads ready for weighing and shipping.

The deposition of the sugar in the cherries and the circulation takesplace automatically, and the syrup in contact with the cherries in thedrums replaces the moisture or water content of the cherries with thesugar solution. This replaced water dilutes the syrup moving upwardly ineach drum, so that automatic flow in the system is achieved because ofthe lower density of the solution in the lines 20, 22, 24, '26 and 28and heating chamber 30 than in the lines 12, 14 and 16. In each drum thesaturated sugar solution flows down along the inclined bottom of thedrum and diffuses upwardly through the cherries in the lowercompartment, then through the lower perforated shelf and the layer ofcherries in the intermediate'compartment and finally through the upperperforated shelf and the layer of cherries in the upper compartment ofthe drum. The perforated plate shelves 40 and 42 provide threerelatively thin layer-like bodies of cherries in each drum, therebyfacilitating distribution of the syrup upwardly through the layers ofcherries and preventing crushing and matting of the cherries.

The heating of the solution in the chamber 30 to a temperature of fromto P. not only releases the ,air content of the solution but decreasesthe density of the column flowing toward the chamber 10. While theheating in the chamber 30 maybe discontinued after the solution becomesclear in the chamber 10, it is, however,

preferably continued to facilitate the flow by increasing phur dioxide.The cherries subjected to the process after pretreatment contained nosugar and they were drained and filled into the drums after insertingthe perforated shelves. Each drum was filled with 367 lbs. of drainedcherries for a total of 6,239 lbs. for the run.

After the seventeen (17) filled drums were connected into the lines, thesystem, including the drums, was filled with water and the cherries wereprocessed for a period of 12 days in accordance with the proceduredescribed above. At the end of that time the maraschino cherriesproduced in the drums were weighed, giving a total weight of 7,286 lbs.for a net gain of 1,047 lbs., or a gain of approximately 16 /z%. Thesugar solids content of the cherries was approximately 45%, and thecherries were round, plump and firm and had an excellent appearance andcolor. The texture of the cherries was crisp, firm and tender. The netgain of approximately 16%, as reported in the above example, is incontrastto the usual increase of only a few percent in conventionalprocesses of manufacturing maraschino cherries, in which a processingperiod of about 6 weeks is used. The increased yield obtained and theexceptional quality of the maraschino cherries produced may be theresult of the combination of conditions employed, particularly theeffective removal of air from the fruit in the initial stages of theprocess and the use of an air-free solution for syruping the fruit. Theheating of the solution returning to the chamber 10 from 130 to 150 F.effectively removes the air content of the returning solution, and thesolution in the chamber 10 is maintained in a quiet unagitated conditionso that no air is taken up in dissolving the sugar. The heated solutionis at the top of the chamber and therefore eddying currents in thechamber are avoided. At the same time the sugar dissolves gradually inthe warm solution at the top of the chamber and gravitates slowly ascirculation proceeds. The air content of the cherries including that inthe tissues is effectively removed, thereby increasing the tissue spaceavailable for receiving the sugar solids from the solution.

The pressure effects achieved in the system in connection with thetemperatures and syrup concentrations employed are also regarded asimportant in obtaining the results reported above. In the first instancethere is the osmotic pressure of the sugar solution applied against thetissues of the fruit. In the process this pressure is kept low by slowlyand imperceptibly increasing the strength of the syrup at a rate naturalto the cherries, so that the sugar solids content of the cherries isnever more than 2% behind that of the syrup brought in contact with thecherries. The tissues of the cherries are, therefore, not broken and thecherry structure is maintained. In the second place there is a pressureeffect caused by the buoyancy of the cherries in the syrup, particularlyin the initial stages of the process when the cherries have aconsiderable content of air, not only in the pit cavities, but in thetheir tissues. This pressure effect is almost entirely avoided by theearly removal of air and to some extent by the layering of the cherriesin the drums, so that the depth of cherries is never more than 8 inches,and usually less. The very small difference of only about 2% in sugarsolids between the syrup and cherries also reduces the buoyancy, whichmight be very great where there is a great differential between thesugar solids in the cherries and syrup.

The air in the cherries, particularly in the initial stages of theoperations tends to increase the buoyancy of the cherries which mightunder other circumstances cause them to float to the top of the layer,but the liquid column in the system, for example 15 feet high, creates apressure effect of approximately 7 lbs. above atmospheric pressure inthe drums. This compresses the air initially in the cherries, so thatthe volume is greatly reduced and correspondingly reduces the buoyancyof the cherries. The air in the cherries is gradually dissolved andreplaced in the manner described above by the air-free syrup penetratingthe cherries. The process is a gentle osmotic exchange which leastaifects the cells and tissues of the cherries. Although the process isgentle, it is so thorcugh, rapid and complete in removing the air fromthe cavities and cell tissues that the finished cherries appeartranslucent as though candied. However, no heat had been applied in theprocess.

Experience in the operation of the process has shown that an increase inweight of approximately 16% is obtainable for cherries processed tobetween 45 and 50% sugar, while cherries processed to higher sugarcontents show correspondingly higher yields.

It is to be understood that the process of the present invention may becarried out in apparatus somewhat differently arranged from thatdescribed, so long as the pressure, temperature and air removal featuresare employed in connection with the differential gravity flow system.Howeventhe drums with removable heads are preferably used because of theconvenience in handling, charging and preparing for shipment.

I claim:

1. In a process for preserving cherries and manufacturing maraschinocherries in which the cherries after being pitted and pretreated forsyruping are contacted by a sugar solution to deposit sugar in thecherries, the improvement comprising providing a body of granulatedsugar in a sugar solution chamber in contact with a water solution ofsugar, providing a body of cherries to be preserved in a contact zone ata substantially lower elevation than that of said chamber, continuouslyrecirculating a stream of sugar solution from the bottom of said chamberto the bottom of said contact zone containing the cherries to bepreserved and back to the sugar solution chamber, passing the stream ofsugar solution passing through the contact zone upwardly through thebody of cherries therein and gradually replacing the moisture andaircontent of the cherries with sugar solution, removing the absorbedair from the stream of recirculated sugar solution as it flows from thecontact zone into the chamber, continuing the recirculation of the sugarsolution through the contact zone and sugar solution chamber,progressively increasing the sugar content of the solution and the sugardeposited in the cherries in the contact zone until they containapproximately 50% by weight of sugar solids, and controlling the sugarcontent of the sugar solution flowing to the contact zone with respectto the sugar solids content of the cherries throughout the period ofcirculation of sugar soluticn to prevent substantial breaking of thetissues of the cherries, thereby producing preserved maraschinocherries.

2. The process of manufacturing maraschino cherries as claimed in claim1, including the step of heating the stream of sugar solution passingfrom the upper part of the contact zone to the upper part of thesaturating solution chamber, during the initial stages of the process toa es ae sugar solids'in-the cherries, the improved process comprisinginitiallyfillingrthe contact zone containing the cherries to beprocessed and thesugar solution zone with-water, introducing sugar'intothe water in thesugar solution zone to form a sugar solution, passingsugar solution from the sugar solution zone intothe lower portion of thecontact zone and upwardly through the cherries therein therebydisplacing the water from the contact zone, passingthe water displacedfrom the contact zone into the sugar solution zone-to form sugarsolution therefrom, continuously recirculating the sugar solutionthrough the cherries in the contact zone and the sugar solution zone andabsorbing the air from the cherries, progressively increasing the sugarcontent of the recirculated sugar solution in the sugar solution zonefor flow-to the contact zone during the recirculation, removing the vairabsorbed from the cherries by the Solutionduringthe-recirculation and asthe solution flows from the contact zone to the sugar soIutionzone-continuingthe. recirculation of the sugar solution throughsaidnzones until the cherries in the contact zone contain approximately50% by weight of deposited sugar solids, and controlling the sugarcontent of the sugar solution flowing to the contact zone with respectto the sugar solids contentof the cherries throughout the period ofcirculation of the sugar solution to prevent substantial breaking of thetissues of the, cherries.

4. ,The processof manufacturing maraschino cherries as claimed in claim3, in which the sugar solution in the contactzone is at normal roomtemperature, and heating the sugar solution flowing from the contactzone to the sugar solution zone to a temperature of from 130 to 150 F.,thereby facilitating the removal of the absorbed air rom thesugarsolution flowing from the contact zone.

5., In .a process for pr serving fruit by -syruping,,in which the fruitafter being prepared for syruping is contacted by a sugar solution todeposit sugar in, the :fruit, the improvement comprisingproviding a bodyof Sugar solution in a solution chamber, providing a body of the fruitto be. preserved in a contactzone, circulating sugar solution from thesugar solution Chamber to and through the contact zone in contact withthe fruitto .be preserved and back to the sugar solution chamber,recirculating the solution through the chamber and zone, absorbing andreplacing themoisture and air content of the fruit with sugar solutionflowinginto and through the contact zone, removing the absorbed air from,the sugar solution flowing fromthe contact zone into thesolutionchamber, starting the syruping of'thebody of fruit with, a dilute sugarsolution, progressively and gradually increasing the sugar content ofthe solution as the recirculation continues and simultaneously graduallyincreasing the sugar content of the fruit, continuing the recirculationof the sugar solution from the sugar solution chamber to and through thecontact zone in contact with the fruit. and back to chamber for a,considerableperiod of time-and until the sugar content of the fruit issufficient to, preserve the fruit, maintaining the sugar content ,ofthesolutionflowing to the contact zonersomewhatabove that of the fruittherein during the recirculation of the solution, and controlling thesugar content of the sugar solution flowing tothe contact zone withrespect to the sugar solids content of the fruit throughout the periodof circulation of the sugar solution to prevent substantial breaking ofthe tissues of the fruit.

6. The process of preserving fruits, comprising the steps of providing abody of the fruit to be preserved in a contact zone, providing a body ofsugar solution at an elevation above the contact zone, conducting astream of solutionrfrom said ;body of solution to the bottom of thecontact zone and causing it to flow upwardly through the body of fruittherein at normal room temperature, passing a stream of solution fromthe upper portion of the contact zone upwardly and delivering it intothe upper portion of the elevated body of sugar solution, said body ofsolution being located at an elevation above the contact zone suflicientto provide a pressure in the contact zone equal to approximately 7pounds per squareinch gauge, heating the solution flowing from thecontact zone'to the elevated body of solution to a temperature of fromto F., maintaining the concentration of the solution flowing from saidbody above the concentration of thesolution flowing from the contactzone for a major portion of the duration of the process, continuing thecirculation ofthe sugar solution from the body of sugar solution to thecontact zone, through the fruit therein andback to the body of sugarsolution for a period of time sufiicient to deposit sugar in the tissuesof the fruit amounting to approximately 50 of the Weight of thepreserved fruit, and controlling the sugar content of the sugar solutionflowing to the contact zone with respect to the sugar solids content ofthe fruit throughout the period of circulation of the sugar solution toprevent substantial breaking of the tissues of the fruit. 7

7. In the manufacture of preserved fruits containing deposited sugar, inwhich the fruit after being prepared for syruping is contacted with asugar solution to deposit sugar in the fruit, the process comprisingproviding a sugar dissolving zone, providing a plurality of drumsarranged in parallel and at a lower elevation than the dissolving zone,filling the fruit to be preserved into the drums, connecting the dnlrnsin parallel for syrup flow from and to the sugar dissolving zone,filling the drums and the zone with water to a given level in the zone,plac ing granulated sugar in the water in the sugar dissolving zone'toform a sugar solution, passing sugar solution formed in the dissolvingzone in parallel streams simultaneously to the lower portions of saiddrumsiand in contact with the fruit therein, causing the sugar solutionin each of the drums to flow upwardly through the, fruit in the drums totake up the moisture and air content of the fruit and deposit sugar inthe fruit, passing a stream of diluted sugar solution from the upperportion of each drum, removing the dissolved air frcm the sugar solutionflowing from all of said drums and passing the solution into the upperportion of the sugardissolving zone, continuously recirculating thesugar solution through the fruitv in the drums and through thedissolving zone, progressively increasing the sugar content of thecirculated sugar solution flowing to the drums during the recirculation,continuing the recirculation of the sugar solution until the fruit inthe drums contains approximately 50% by weight of sugar solids, andcontrolling .thelsugar content of the sugar solution flowing to thedrums with respect to the sugar content of the fruitthroughcutthe periodof circulation of the sugar solution to prevent substantial breaking ofthe tissues of the fruit.

8. The manufacture of preserved fruits as claimed in claim 7, in whichthe sugar solution flowing to the drums at the start of the syrupingoperation contains approxibody of sugar solution in a solution zone,providing bodies of fruit in aplurality of drums arranged in parallel,connecting the drums in parallel for syrup flow from and to the solutionzone,'con ducting solution from said body of solutionin parallel streamsrespectively to the bottoms of the drums and causing it to flow upwardlythrough the bodies of fruit therein to dissolve air and moisture fromthe fruit and deposit sugar in the fruit, passing streams ,of solutionrespectively from the upper portions of the drums and delivering thesolution into the upper portion of the 9 body of solution in thesolution zone, heating the solution flowing from the drums to the bodyof solution to a temperature of from 130 to 150 F. and removingdissolved air therefrom, circulating substantially air-free solutionfrom the solution zone to the drums, maintaining the concentration ofthe solution flowing from said body of solution above the concentrationof the solution flowing from the drums for a major portion of theduration of the process, continuously recirculating the sugar solutionthrough the fruit in the drums and through the solution zone includingthe passage of substantially air-free sugar solution through the fruitfor a period of time sufiicient to deposit sugar in the tissues of thefruit amounting to at least about 50% of the weight of the preservedfruit, and controlling the sugar content of the sugar solution flowingto the drums with respect to the sugar content of the fruit throughoutthe period of circulation of the sugar solution to prevent substantialbreaking of the tissues of the fruit.

11. In the manufacture of preserved fruits containing deposited sugar,in which the fruit after being prepared for syruping is contacted with asugar solution to deposit sugar in the fruit, the process comprisingproviding a sugar dissolving zone, providing a plurality of drumsarranged in parallel and at a lower elevation than the dissolving zone,filling the fruit to be preserved into the drums, connecting the drumsin parallel for syrup flow from and to the sugar dissolving zone,filling the drums and the zone with water to a given level in the zone,placing granulated sugar in the water in the sugar dissolving zone toform a sugar solution, passing sugar solution formed in the dissolvingzone in parallel streams simultaneously to the lower portions of saiddrums and in contact with the fruit therein, causing the sugar solutionin each of the drums to flow upwardly through the fruit in the drums totake up the moisture and air content of the fruit and deposit sugar inthe fruit, passing a stream of diluted sugar solution from the upperportion of each drum, removing the dissolved air from the sugar solutionflowing from all of said drums and passing the solution into the upperportion of the Sugar dissolving zone, continuously recirculating thesugar solution through the fruit in the drums and through the dissolvingzone, progressively increasing the sugar content of the circulated sugarsolution flowing to the drums during the recirculation, continuing therecirculation of the sugar solution until the fruit in the drumscontains approximately by weight of sugar solids, and controlling thesugar content of the solution flowing to the drums to maintain thesolution only about 2% above the sugar content of the fruit during thesymping operation.

References Cited in the file of this patent UNITED STATES PATENTS2,169,362 Lachman Aug. 15, 1939 2,209,889 Lachman July 30, 19402,236,692 Neil Apr. 1, 1941 2,785,071 Mathews Mar. 12, 1957 2,848,333Fisher Aug. 19, 1958 FOREIGN PATENTS 297,927 Great Britain Oct. 4, 1928UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,032,419 May 1 1962 Dean J. Limpert It is hereby certified that errorappears in the above numbered patant requiring correction and that thesaid Letters Patent should read as corrected below.

Column .3 line 64 for "introduction" read column 5 line 67 strike out"saturating" production strike out "the"; column 6 line 64 Signed andsealed this 4th day of September 1962o (SEAL) Attest:

ERNEST w. SWIDEF. DAVID LADD Attesting Officer Commissioner of Patents

1. IN A PROCESS FOR PRESERVING CHERRIES AND MANUFACTURING MARASCHINOCHERRIES IN WHICH THE CHERRIES AFTER BEING PITTED AND PRETREATED FORSYRUPING ARE CONTACTED BY A SUGAR SOLUTION TO DEPOSIT SUGAR IN THECHERRIES, THE IMPROVEMENT COMPRISING PROVIDING A BODY OF GRANULATEDSUGAR IN A SUGAR SOLUTION CHAMBER IN CONTACT WITH A WATER SOLUTION OFSUGAR, PROVIDING A BODY OF CHERRIES TO BE PRESERVED IN A CONTACT ZONE ATA SUBSTANTIALLY LOWER ELEVATION THAN THAT OF SAID CHAMBER, CONTINUOUSLYRECIRCULATING A STREAM OF SUGAR SOLUTION FROM THE BOTTOM OF SAID CHAMBERTO THE BOTTOM OF SAID CONTACT ZONE CONTAINING THE CHERRIES TO BEPRESERVED AND BACK TO THE SUGAR SOLUTION CHAMBER, PASSING THE STREAM OFSUGAR SOLUTION PASSING THROUGH THE CONTACT ZONE UPWARDLY THROUGH THEBODY OF CHERRIES THEREIN AND GRADUALLY REPLACING THE MOISTURE AND AIRCONTENT OF THE CHERRIES WITH SUGAR SOLUTION, REMOVING THE ABSORBED AIRFROM THE STREAM OF RECIRCULATED SUGAR SOLUTION AS IT FLOWS FROM THECONTACT ZONE INTO THE CHAMBER, CONTINUING THE RECIRCULATION OF THE SUGARSOLUTION THROUGH THE CONTACT ZONE AND SUGAR SOLUTION CHAMBER,PROGRESSIVELY INCREASING THE SUGAR CONTENT OF THE SOLUTION AND THE SUGARDEPOSITED IN THE CHERRIES IN THE CONTACT ZONE UNTIL THEY CONTAINAPPROXIMATELY 50% BY WEIGHT OF SUGAR SOLIDS, AND CONTROLLING THE SUGARCONTENT OF THE SUGAR SOLUTION FLOWING TO THE CONTACT ZONE WITH RESPECTTO THE SUGAR SOLIDS CONTENT OF THE CHERRIES THROUGHOUT THE PERIOD OFCIRCULATION OF SUGAR SOLUTION TO PREVENT SUBSTANTIAL BREAKING OF THETISSUES OF THE CHERRIES, THEREBY PRODUCING PRESERVED MARASCHINOCHERRIES.